Support sharing of ContentMain and BrowserMain code with embedded use cases.

content/shell/shell_win.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/shell/shell.h"
 
 #include <windows.h>
 #include <commctrl.h>
 
 #include "base/message_loop.h"
@@ skipping 210 matching lines @@
           shell->Reload();
           break;
         case IDC_NAV_STOP:
           shell->Stop();
           break;
       }
       break;
     }
     case WM_DESTROY: {
       delete shell;
-      if (windows_.empty())
+      if (windows_.empty()) {
+#if defined(TEST_EMBEDDED_MESSAGE_LOOP)
+        // Running our own message loop so quit normally.
+        PostQuitMessage(0);
+#else
         MessageLoop::current()->Quit();
+#endif
+      }
       return 0;
     }
 
     case WM_SIZE: {
       if (shell->GetContentView())
         shell->PlatformResizeSubViews();
       return 0;
     }
   }
 
@@ skipping 20 matching lines @@
 
         return 0;
       }
   }
 
   return CallWindowProc(shell->default_edit_wnd_proc_, hwnd, message, wParam,
                         lParam);
 }
 
 }  // namespace content